1. Field of the Invention
This invention relates to curable blends and more specifically, it relates to improved curable blends of chloroprene polymer and ethylene copolymer.
2. Description of the Prior Art
Elastomers are frequently compounded with softeners and plasticizers to extend their applicability to different end uses. Many of these softeners are liquids which can volatilize on exposure of the compound to elevated temperatures or can be extracted when the compound is exposed to solvents or oils. More permanent polymeric liquid plasticizers are relatively expensive.
Research Disclosure No. 13816, dated October, 1975, discloses that the oil resistance of chlorosulfonated polyethylene was found to be significantly improved for blends in which a terpolymer (30-45 wt. % terpolymer based on the elastomer) of ethylene/carbon monoxide/vinyl acetate was used in place of ethylene/vinyl acetate copolymer. It is also stated therein that sealants with excellent tack and rubberiness were obtained with blends of an ethylene/carbon monoxide/vinyl acetate terpolymer with butyl rubber.
U.S. Pat. No. 3,780,140 discloses terpolymers of ethylene/carbon monoxide/termonomer and blends of same with a compatible amount of at least one solid organic polymer. Various termonomers are disclosed, such as unsaturated mono- and dicarboxylic acids, esters of such acids, vinyl esters of saturated carboxylic acids, vinyl alkyl ethers, acrylonitrile, etc. Solid organic polymers are disclosed to have preferably polar characteristics in order to obtain compatibility on a molecular scale. Such polymers can be polyamides; cellulose derived polymers; vinyl halide polymers; alpha-olefin based polymers such as polyethylene, polypropylene, chlorosulfonated polyethylene; ethylene-vinyl ester copolymers; polymers of styrene; polymers of acrylonitrile and copolymers of at least 40% acrylonitrile and other ethylenically unsaturated comonomers such as vinyl acetate, vinyl chloride and isobutylene; acrylics, polyesters; polyurethanes; polycarbonates; phenolics; polysulfones; epoxy resin; chlorinated polyethers; alkyd resins; acetal resins; ABS resins; silicone resins; tars; waxes; etc.
U.S. Pat. No. 2,495,286 discloses copolymers of ethylene and carbon monoxide with one or more additional polymerizable organic compound such as other olefins, butadienes, vinyl and vinylidene compounds, vinyl esters, styrene, acrylic and methacrylic acids and their esters, etc.
U.S. Pat. No. 3,873,494 discloses curable blends and vulcanizates of 100 parts of an ethylene/alkyl acrylate or alkyl methacrylate copolymer or an ethylene/alkyl acrylate or methacrylate terpolymer wherein the termonomer among others can be carbon monoxide, with 1-30 parts of a butadiene/acrylonitrile polymer. The termonomer is present in an amount not higher than about 10 wt. percent of the terpolymer.